Electrode



Patented Apr. 27, 1926,

UNITED STATE PAraur Fries.

VICTOR YNGVE, 0F LONG BRANCH, NEW JERSEY, ASSIGNOR T0 MANHATTAN ELEC-TRICAL SUPPLY COMPANY,.INC., OE NEW YORK, N. Y., A CORPORATION OFCHUSETTS.

No Drawing.

1 '0 all whom it may 0012 0am:

Be it known that I, VIo'roR YNGVE, a citizen of the United States,residing at Long Branch, New Jersey, in the county of Monmouth andStateof New Jersey, United States of America, having invented certain new anduseful Improvements in Electrodes, do hereby declare that thefollowingis a full, clear, and exact description of the same.

This invention relates to new and useful improvements in electrodes forbatteries and more particularly to metallic electrodes for dry cells.-

It is the object of the present invention to provide a metallicelectrode which will not be corroded locally before being placed inactual service, the shelf life. of whichis long, and which isnevertheless inexpensive.

to manufacture and assemble.

It is well known in this art that local corrosion of the metallicelectrode is one of the chief reasons for short shelf life. Thiscorrosion is caused by an uneven electrolytic potential on the surfaceof the electrode, the Zinc dissolving in one area being deposited inanother, thus pitting the surface, with the result that when the cell isplaced in service it isperforated at the thin areas, with resultant lossof electrolyte and ruin' ofthe cell. The uneven electrolytic potentialis caused by impurities in the electrode or physical unevenness orstrain in the elec-, trode. In zinc cups for dry cells, for instance, ithas been found that the zinc is more quickly consumed along seams and atpoints subjected to excessive strain during the rolling, drawing orother similar operatrons Most of this local corroslon 1s due to localaction before the battery is actually.

MASSA- ELECTRODE.

Application filed July 30, 1923. Serial No. 654,783.

or depositing by electrolysis or precipitation. These suggestions werefound impractical because too expensive or ineffective materially toimprove the efficiency and particularly the shelf life of dry cells.Similarly, dry cells which remain inactive while in stock, the so-calledreserve cells, are too expensive or are in other ways objectionableinucomparison with the usual type of dry ce In accordance with thepresent invention, these disadvantages are avoided by forming themetallic electrodes, e. zinc cans of dry cells in the usual manner andthen electrolytically depositing thereon a thin film of the same metal,e. g. zinc. This film of 7 metal will be of great purity and willpossess a uniform electrical potential and will be free from physicalstrain. It will therefore resist for a relatively long time the localaction to which such electrodes are subjected during the shelf life of adry cell. The application of such a thin film of electrolyticallydeposited metal is inexpensive and may entirely replace the nowgenerally practiced amalgamation of the inside surface of zinc cansalthough, obviously, the present inventionmay be practiced incombination with the usual amalgamating. While it is desirable that thefilm of electrolytically deposited metal be as heavyas is permissiblefrom a cost standpoint, any film which covers the surface will giveimproved results.

What I claim is:

1. The method of protecting zinc containor electrodes for dry cellsagainst local corrosion, which consists in entirely covering the insidesurface thereof with a'thin film of zinc electrolytically depositedthereon.

2. The method of making dry cells which consists in'firs't forming theZinc container electrode, then electrolytically depositing on the insidesurface thereof a thin film of zinc, and finally completing the drycell.

' In witness whereof, I hereunto subscribe my name this 23d dayof July1923.

VICTOR YNGVE.

